Cognomen พิรารัตน์ (พิรารัตน์ 
, Pirarath 
) , globally, is a very rare family name. The surname พิรารัตน์ is habitual in Thailand, where it is a very rare surname, and India, where it is an extremely rare surname. More frequently, พิรารัตน์ is the forename as well as the last name.